Sweet Potato Falafel with Tahini Sauce

I miss falafel. I used to get fresh falafel pitas at a great Mediterranean cafe. The owner was half Syrian and half Italian and he made the most amazing food. When you broke open his falafel they were green on the inside, which was slightly alarming at first because I was used to the boxed stuff. But it tasted so good - not dry, and the tahini sauce that was served over top was terrific.